Arrangement for producing and receiving short waves



Sept. 10, 1935. w. WEIHE 2,013,773

ARRANGEMENT FOR PRODUCING AND RECEIVING SHORT WAVES Original Filed July 8, 1930 IINVENTOR WERNER WElHE BY lv /w u.

ATTORNEY Patented Sept. 10, 1935 UNETED STATES PATENT FFIQE ARRANGEMENT FOR PRODUCING AND RECEIVING SHORT WAVES tion of Germany Application July 8, 1930, Serial No. 466,422.

Renewed March 21, 1935. In Germany July 9 12 Claims.

It is known to produce very short electric waves by means of a three-electrode tube in the manner that the intermediate electrode is impressed with a constant relatively high potential and the outer electrode in comparison thereto with a smaller positive or even negative potential with respect to the cathode. The frequency produced depends partly from the tube dimensions and the potentials impressed, partly from the data of the external oscillation circuit. It is evident that the production of the oscillations is based upon the pendulum movement of the electrons in the vacuum tube.

It is known to use arrangements of this type 1 also for the reception of short waves. It is necessary in this case in order to insure an undistorted reception that the intensity of the oscillations, particularly towards the smaller values, can be changed at will. This may be accomplished as such by a variation of the electric operating conditions, for instance by one of the direct current potentials, but the adjustability of the receiver is rendered very difficult in that case due to the change in thewave length occurring at the same time. Particular difiiculties are encountered to vary thereby the intensity of the oscillations in continuous manner down to zero.

In accordance with the invention and in order to avoid these disadvantages the intensity of the 301 oscillations is controlled by means of magnetic fields in the manner that at the same time frequency changes are prevented to a great extent. For this purpose, the magnetic field is arranged in the manner that there exists a component of 35 the magnetic field at right angles to a plane which is imagined as being disposed through the longitudinal axis of symmetry of the electrode system. Although for purposes of illustration I have chosen a magnetic field having a component 40 at right angles with a plane passed through the axis of the electrode tube, it Will be appreciated that said component may be at any angle with respect to said plane without departing from the spirit of the present invention. For the prefer- 5. ably continuous variation of the oscillation intensity provisions are made thereby that the intensity or direction or both of these properties of the magnetic field are to be changed. The mode of operation of the arrangement must in 50-. this case evidently be explained by the fact that according to the selection of intensity and direction of the magnetic field a more or less larger part of the electrons, namely those whose paths form with the magnetic lines of force a larger an- 55 gle, are varied in their pendulum-frequency with the result that only a non-influenced residual part of electrons is decisive for the oscillation intensity. Experiments on which the invention is based have proven that the indicated changes of the oscillation intensity are possible without 5 having noticeable wave variations occur and that a continuous change of the intensity may be effected down to zero value.

The production of the required magnetic field may be accomplished in any desired manner: 10

thus for instance by means of a permanent magnet or by means of an electromagnet with or without iron core. The variations in intensity and direction may for instance be effected by the change of the distance of the magnetic ar- 15 rangement from the tube or its rotation, but also by other means. Thus there is obtained for instance in the use of an electromagnet a possibility of control by a change in the intensity of its exciting current. The -magnetic field may 20 also be established by the combination of several individually variable or partly constant partly variable magnetic fields.

The described arrangement further offers the possibility to transpose in simple manner the 5 super-regenerative principle used in the case of back-coupled tube receivers also to receiving arrangements which are connected in the said manner. As is known, the super-regenerative principle consists in varying the oscillation intensity in the vicinity of the start of the oscillations in periodical manner suitably in higher than audible frequency sequence. In accordance with the invention, these variations in the intensity of the oscillations are produced by variation of the magnetic field. For this purpose may be employed any means insuring that with a magnetic field produced in any manner intensity or direction or both values can be varied simultaneously in periodic manner. It may be suitable in that case to superpose to this alternating field a direct current field produced in some manner or other. The necessary periodic variations of the magnetic field may for instance be produced in the manner that magnet coils are provided which are traversed by alternating currents. The same result may also be achieved by mechanical periodic longitudinal or rotary motion of the magnetic arrangement relative to the electrode arrangement.

A more complete understanding of the invention may be had from the following detailed description taken in conjunction with the accompanying. drawing wherein:

Figure 1 shows an oscillating circuit arranged in accordance with the present invention;

Figure 2 shows an oscillating circuit as shown in Figure 1 including a thermionic tube having its axis located in a magnetic field;

Figure 2a is a diagram illustrating the various forces applied to the electrons.

Fig. 1 shows one of the circuit possibilities known as such in the art whereby the arrangement according to the invention may be made use of. Therein l is a triode whose intermediate electrode is connected through a choke 3 with the positive pole 4 of a potential source whose negative pole 8 is connected to the filament. The outer electrode is connected across a choke 2 and the primary of an intermediate frequency transformer 5 with the pole of a potential source 6 in the manner that the outer electrode is impressed with a low positive potential in comparison to the intermediate electrode and with respect to the cathode. I is a condenser for the blocking of the outer electrode against the high potential of the intermediate electrode. The oscillating circuit (shown in heavy lines) consists in the example shown of the condenser between outer electrode and intermediate electrode of the triode, the leads to the blocking condenser I and, for certain cases,

of a wire piece I I for the reception of electric oscillations.

Fig. 2 shows an embodiment by way of example of the object of the invention for the case that for the regulation of the oscillating intensity is used an electromagnet variable in the intensity of its energizing current. The drawing represents in part a section through the longitudinal axis of a thermionic tube It) with cylindrical anode Hi and control grid I3 and a straight-line heating filament 12. In this case the straight line heating filament 12 forms the longitudinal symmetrical axis. The filament i2 is surrounded by the cylindrical intermediate electrode 13 and this in turn by the likewise cylindrical outer electrode Hi. In the example shown the magnetic 45 I field is arranged in the manner that the magnetic axis indicated by the arrow is located at right angles to a plane figured as running through the longitudinal axis of symmetry of the system which is the filament l2.

This arrangement of the electrodes in the direction of the longitudinal axis of the tube is best suited for the purpose in case of brake-field connections for the reason that in this manner wide anode cylinders, which have been proven advantageous in brake-field arrangements, may

be disposed in glass bulbs without that the bulbs reach too large dimensions. Considering the supporting means for the electrodes, the length of such a tube can hardly be kept below 60 mm. while the diameter proper of the glass bulb does not have to be more than 36 mm with a correct dimensioning of the anode diameter.

Now, if operated with the same magneto-motive force, the magnetic field force which can be obtained in such a tube is at right angles to the heating filament at least twice as great as in the direction of the filament. This proportion becomes still more unfavorable for fields parallel to the heating filament if the required tube feet are taken in account, besides the considerable constructive difliculties which are encountered in the production of a magnetic field in the direction of the heating filament.

But now, even with equal intensity, a field at right angles to the heating filament is hardly field disposed at right angles to the filament de- 5 fiects in exactly the same way all electrons, even if it takes a little longer. That this is true follows from the following deduction with reference to Fig. 2a. Electrons which oscillate in path I-l' are influenced exactly as above, since for them the field is transverse. Electrons which oscillate along 22' are, true enough, in equilibrium, but not in a stable one. Small deviations, such as they always occur, force the electron step by step from path 22 into path l-l, forcing the electron 15 at the same time out of the plane of oscillation. Since the oscillations occur very rapidly, the path Il, or a path with the component Ii', is reached very quickly. Since, due to above stated reasons, the magnetic field may be made at least twice as strong, with equal energy input than in the case of the pure transverse field, a good effect is quite evident. Fields of less than 10 Gauss are already sufiicient in order to insure the eifect aimed at by the present application. Fields of this type may be produced by means of the smallest and cheapest commercial horse-shoe magnets.

For the production of the magnetic field are provided the coils l5 and I6 which are connected i in series with a potential source II and a variable resistance I 8. By the variation of resistance l8 the possibility is then given to adjust to any desired intensity of oscillation and this continuously down to the zero value.

In order to insure a super-regenerative reception, the potential source I? might for instance be connected in series with a corresponding A. C. current source, if need be with the insertion of a transformer. regenerative frequency is suitably accomplished by means of a tube generator whereby the exciter coils l5, It can at the same time be used as oscillating circuit coils.

Having now described my invention, what I claim and desire to secure by Letters Patent is the following:

Claims:

1. An arrangement for producing or receiving electrical waves comprising a thermionic tube, an anode having a dimension, a cathode having a dimensicn'parallel to said anode dimension, and a control electrode, circuit means for coupling together said anode and control electrodes, means for applying a high positive potential to the control electrode of said tube relative to said anode and cathode and means for subjecting said electrodes to a magnetic field acting transversely to the dimension of said cathode.

2. An arrangement for producing and receiving electrical waves comprising a thermionic tube, a source of potential, an inductance connecting the control electrode of said tube to the positive terminal of said source, a second inductance connecting the negative terminal of said source to 5 the anode electrode of said tube, a second source of potential connected between said negative terminal of said first named source and the filament of said tube, said anode and filament each having a dimension substantially parallel to one another, the negative terminal of said second source being connected to said filament and the positive terminal of said source being connected to the negative terminal of said first source of potential, and means external of the envelope of The production of the super- 40 said tube for producing a magnetic field within which said electrodes are located transversely of the filament of said tube, the axis of which is substantially perpendicular to said filament transversely of said dimensions of said filament and anode.

3. Short wave signalling apparatus comprising a thermionic tube, said tube having a filament in the form or a linear conductor, a control electrode in the form of a cylinder surrounding said conductor and an anode in the form of a cylinder surrounding said control electrode, means for maintaining said control electrode at a positive potential relative to said anode and filament, an oscillating circuit interconnecting said anode and control electrodes, and means for producing a magnetic field transversely of said filament, the axis of which is perpendicular to said filament.

4. Short wave signalling apparatus comprising a thermionic tube, said tube having a filament in the form of a linear conductor, a control electrode in the form of a cylinder surrounding said conductor and an anode in the form of a cylinder surrounding said control electrode, means for maintaining said control electrode at a positive potential relative to said anode and filament, an oscillating circuit interconnecting two of said electrodes, a Work circuit connected with said oscillating circuit and means for producing a magnetic field, the axis of which is perpendicular to said filament.

5. A thermionic oscillation generator and re peater comprising a thermionic tube of the tri ode type, a source of potential, means for connecting the filament electrode of said tube to the negative terminal of said source, inductive means for connecting the anode of said tube to a point on said source, inductive means for connecting the control electrode of said tube to the positive terminal of said source, a capacity connecting both said inductive means, radiating means connected to one of said inductive means, and means for producing a direct current magnetic field, the axis of which is substantially parallel to the shortest line from the filament to the anode.

6. In an electron discharge device circuit having an anode having a dimension, a cathode hav ing a dimension parallel to said anode dimension and a control electrode, said control electrode being at a high positive potential relative to said anode and cathode, the method of obtaining a variation in intensity of oscillations in said circuit without any substantial change in wave length thereof which comprises applying a steady magnetic field running substantially transverse to the dimension of said cathode, and varying the intensity of said field to obtain any desired intensity of oscillations.

'7. An arrangement for producing or receiving electrical waves comprising a thermionic tube having an anode having a dimension, a cathode having a dimension parallel to said anode dimension, and a control electrode, a source of electromotive force for maintaining said control electrode at a positive potential relative to said cathode and anode, and means for applying a magnetic field to said electrodes at an angle to said cathode such that said magnetic field has a component substantially at right angles to said dimension of said cathode, the intensity of said field being variable for varying the intensity of oscillations produced without any substantial change in the Wave length thereof.

8. In an electron discharge device circuit having an anode having a dimension, a cathode having a dimension parallel to said anode dimension and a control electrode, said control electrode being at a high positive potential relative to said cathode and anode, the method of obtaining a variation in intensity of oscillations in said circuit without any substantial change in wave length thereof which comprises applying a constant magnetic field to said electrodes at an angle to said cathode such that said magnetic field has a component substantially at right angles to said dimension of said cathode, and varying the direction of said field to vary the intensity of oscillations.

9. In combination, an electron discharge device oscillator having an anode and an elongated cathode, means for producing oscillations including sources of potential for suitably energizing said anode and cathode electrodes, and means for applying a magnetic field to said electrodes with a component substantially at right angles to the length of said cathode.

10. In combination, an electron discharge device oscillator having anode, an elongated cathode, and control electrodes, means for suitably energizing said electrodes to produce oscillations, and means for applying a magnetic field to said electrodes with a component substantially at right angles and perpendicular to the length of said cathode.

11. In combination, an electron discharge device regenerative oscillator having anode, an elongated cathode and control electrodes, means for producing oscillations by regeneration including one or more sources of potential for suitably energizing said electrodes, and means for applying a magnetic field to said electrodes with a component substantially at right angles to said cathode, the axis of said component being perpendicular to the length of said cathode.

12. In combination, an electron discharge device oscillator comprising an anode having a dimension, a cathode having a dimension parallel to said anode dimension, means for producing oscillations including sources of potential for suitably energizing said anode and cathode electrodes, and means for applying a magnetic field to said electrodes with a component substantially at right angles to the dimension of said cathode.

WERNER WEII-IE. 

